Add crop bounds validation for split XML IPD implementation

[Copilot]

Description of the Changes You Made

Adds validation to catch invalid crop bounds before Dask raises IndexError. When crop bounds exceed array dimensions after transpose, the error message was cryptic. Now validates early with clear diagnostics.

Validation checks:

• crop_min[i] >= 0 (non-negative bounds)
• crop_max[i] < array_shape[i] (within dimensions)
• crop_min[i] <= crop_max[i] (valid range)

Error messages now include:

• Which dimension failed
• The invalid value
• The actual array shape

# Before: IndexError from Dask with no context
# After: ValueError with clear message
raise ValueError(
    f"crop_max[0]=15 exceeds array dimension 0 "
    f"(shape=10); crop_max must be < array shape"
)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Instructions for Testing

Run python tests/test_detection/test_image_reader.py - includes 3 new test cases covering each validation scenario.

Additional Info

Addresses feedback from PR #167: #167 (comment)

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